In most cases people carefully unseal the box and than seal it back if they need to sell. Certainly they have to maintain the unit's cosmetic condition as new. By default, the unit that left the territory of audio dealer is used even if it was never used.
I don't know about Mac but most of the companies will not transfer the warranty. The only company I know is Bryston but truly, since it produces the high mass products for pro- amplification movie-theater amplification they don't realy care about home audio/video consumers in terms of loosing or gaining the business as much as other manufacturers that solely produce home audio/video products.
If I were the small manufacturer such as Unison Research or EAR I wouldn't ever give a warranty on the used product because I would ruin my business.
I don't know about Mac but most of the companies will not transfer the warranty. The only company I know is Bryston but truly, since it produces the high mass products for pro- amplification movie-theater amplification they don't realy care about home audio/video consumers in terms of loosing or gaining the business as much as other manufacturers that solely produce home audio/video products.
If I were the small manufacturer such as Unison Research or EAR I wouldn't ever give a warranty on the used product because I would ruin my business.